She is known for her work on the North American adaptation of Being Human and for her substantial contributions to Greg Berlanti's and The CW's Arrowverse, including being the showrunner of DC's Legends of Tomorrow.

[3] She is an emphatic Batman fanatic, and attributes comic book and television writer Paul Dini as being a notable favorite interpreter.

[4] She also counts John Ostrander, Alan Moore, Kurt Buslek, Frank Miller and Chris Claremont as being influential to her writing.

She went on to become a writer on the show, scripting three hours ("Dream Reaper", "I'm So Lonesome I Could Die", "Of Mice and Wolfman") of the paranormal drama.

She and Coburn co-penned the season's mid-season finale "The Climb", which fully introduced supervillain Ra's al Ghul (Matt Nable).

It showcased the DC superhero Firestorm (Robbie Amell(Ronnie Raymond)/Victor Garber(Professor Martin Stein)) and featured the first spoken words of supervillain Gorilla Grodd.

[5] During the 2015 Winter Television Critics Association tour, The CW announced a new 6-part animated series, Vixen, centered around the DC heroine.

The series is written by Shimizu, Arrow showrunner Wendy Mericle, Brian Ford Sullivan, and comic book writer Lauren Certo.